Completely possible. And if we're not looking at 1 object (or a body) moved from vehicle to vehicle, but rather 2 (or more) different objects, each in a separate vehicle, that makes much more sense to me. I suppose it's even possible that part of the crime occured in one of these vehicles, although perhaps not the actual death itself (I so hate typing that out), and that evidence related to clean up was in the other car.
What I'm finding so hard to wrap my brain around is how one tiny body could leave evidence over such a wide area? 2 cars, a landfill, a dump site, a house, a yard. I'm just not getting something here...or my brain just doesn't WANT me to "get it".